


Who Said Cheaters Never Prosper?

by julieschmulie



Series: Black Eagles Girls and Gays [5]
Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Autistic My Unit | Byleth, F/F, Fluff and Smut, Porn With Plot, Praise Kink, Sort Of, Top My Unit | Byleth, Trans Female Character, Trans My Unit | Byleth, Vaginal Fingering
Language: English
Status: Completed
Published: 2021-02-10
Updated: 2021-02-10
Packaged: 2021-03-16 00:00:36
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,211
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29322828
Author URL: https://archiveofourown.org/users/julieschmulie/pseuds/julieschmulie
Summary: Byleth and Edelgard have been known to make small bets on whether or not their friends would end up together. However, when Bernadetta and Petra's budding relationship becomes the subject of a wager, someone puts their finger on the scale.
Relationships: Background Bernadetta von Varley/Petra Macneary, Edelgard von Hresvelg/My Unit | Byleth
Series: Black Eagles Girls and Gays [5]
Series URL: https://archiveofourown.org/series/2207628
Comments: 3
Kudos: 58





	Who Said Cheaters Never Prosper?

**Author's Note:**

> Context: This happens in the universe of one of my other fics, which you can read here (https://archiveofourown.org/works/22609708/chapters/54035209). It's not crucial for understanding this one, but it's there if you're interested. Thanks!

The Adestrian war caravan rolled through Magdred territory, padding through the rolling foothills and grass. The assault on Arianrhod had been a difficult one, one that ended with the city being leveled by javelins of light, destroying what remained of House Rowe and the Silver Maiden alike. The Black Eagle Strike force was eager to get home, having only a few hours more riding left.

In the center of the army rode Emperor Edelgard von Hresvelg’s Black Eagle Strike force, most of them out of the carriages and on horseback to enjoy the warm weather. Edelgard and Byleth rode in the back, side by side. Byleth clicked her tongue at her horse, Trout, and reached forward with a sugar cube. He took it from her hand, ruffling his ears appreciably. 

“I am glad we are almost home,” said Edelgard. “I am ready to sleep in a proper bed.”

“Me as well. My cot is comfortable, but I miss proper feather pillows,” said Byleth. She swept the hills as they rode, an eye out for any threats. The ride had been calm, but you could never be too careful.

“It amuses to me to no end how much you enjoy your simple luxuries,” said Edelgard, smiling slightly. “For a former mercenary you have a good appreciation for the finer things of life.”

“I learned to value them on the road. Nice clothes, good wine, excellent tea. it all came and went with our money. I tried to enjoy nice things when I could,” said Byleth. 

“Understandably. I can imagine the absence made the heart grow fonder.”

“Did you know that expression has mutated over time? The original phrase was ‘Always toward absent lovers love’s tide stronger flows.'”

“Truly? I did not know.” 

“I first read it in a book of poetry I had stolen from one of Jeralt’s other mercenaries. I quoted it in front of Professor Hanneman once and he went on a literature based lecture then and there. It was quite interesting.” 

“I can imagine he was pleased to find someone to tell that to,” chuckled Edelgard. “You’ll have to read me some poetry. You have a lovely voice for it.”

“Thank you,” said Byleth. Her voice did not betray her, but she felt embarrassed at Edelgard’s compliment. While her heart did not flutter or pound the way Dorothea spoke of when talking about her romance with Ingrid, she felt something in her chest twinge. 

Ahead of them, Bernadetta and Petra rode side by side. The cadence of Petra’s voice was barely audible on the wind, and Byleth could see that Bernie was listening closely.

“They are adorable, are they not?,” said Edelgard. Byleth nodded. 

“Quite. I wonder when they will finally begin to date,” she said. When she had come back from her sleep it had been clear something had shifted between the two. They hovered close to one another, shared quiet moments, and a few times she had seen Petra nearly take Bernie’s hand before hesitating.

“I should hope soon. They’ve been dancing around it for years,” said Edelgard. “I suppose it’ll be whenever Petra makes her move. I saw she’s been working on a necklace for Bernadetta.”

“You think Petra will be the one to ask?,” said Byleth. “I am of the opinion that Bernie will ask first. She’s been getting her courage together to do it for awhile, now.”

“Professor, be honest. I adore Bernadetta as much as you do, but Petra is clearly going to be the one to broach the topic.”

“I think you underestimate Bernie.”

“Is that so? Then how about a little wager?” Edelgard smiled like a cat at Byleth. It was a tradition they had started up after the mission to Ailell, when Dorothea had insisted on coming to Ingrid’s defense. Edelgard had at first been galled by the suggestion, but it soon became a harmless way for the pair to make speculations on who would end up dating whom. After winning the first bet on a long shot by betting on Ingrid, she had become hooked.

“You’re on,” said Byleth, smiling softly. “What are the conditions?”

“Hmm,” said Edelgard. “I think it should be the first to make a romantic move. A gift, a kiss, a confession. Whichever comes first.”

“So you intend to win when Petra gives Bernie the necklace?”

“Perhaps,” chuckled Edelgard. 

“You know what, I’ll take those odds. I believe in Bernie. The usual stakes?”

“Of course. I’ll enjoy taking your gold piece, Professor,” said Edelgard.

“Oh, you are absolutely on,” said Byleth. “May the best guess win.”

* * *

The dining hall bustled as Byleth shoveled food into her mouth. She had been advised to maintain a modicum of respectability while dining with the Emperor, and as such had decided to use a napkin properly rather than stuffing it into her collar. She didn’t understand the insistence on separate forks for courses, but it was a small price to keep Hubert from lecturing.

Edelgard, Caspar, Linhardt, Hubert, and Bernadetta sat with her, all chatting about the recent battle and tactics. She was mostly quiet, interjecting occasionally with an observation or quip. When she had first started to dine with her former students it had felt odd. She had been mostly quiet, afraid to potentially upset someone unintentionally or say something in jest that most people couldn’t discern as a joke. She had slowly been pulled out of her shell, and now felt comfortable eating with her friends.

“Bernadetta!!,” shouted Caspar, startling the poor girl. His voice boomed despite his mouth being half stuffed with chicken. “I’ve been meaning to ask you, can you help me learn to shoot a bow? I saw you knock those Rowe Pegasus Knights out of the sky, it was so cool!”

“Caspar, I thought you said ‘Bows are for nerds, I can punch anything I need to kill’?,” said Byleth. She remembered that training session years ago, where she had tried to get him to diversify with a ranged weapon, and he point blank refused. After 20 minutes of exasperated discussion she convinced him to learn to use thrown short-axes.

“I mean… uh… yeah. But I realized! I can’t punch things that are 30 feet in the air! So I’ll shoot them until they fall, and then punch them!,” said Caspar, bouncing back quickly. Hubert rolled his eyes and muttered some curse under his breath, sipping from his coffee cup. 

As she and Caspar talked about lessons Petra slid up behind Bernie, tapping her on the shoulder. Byleth could see she held a package behind her tied up with a red ribbon and cursed internally. She side eyed Edelgard, who looked immensely smug.

“I am sorry Bernie, I am forgetting that you do not hear my footsteps. I brought you something,” said Petra, sitting down by Bernie and handing her the package.

“Thanks, Petra!,” said Bernadetta, her face cracked into a wide smile. “How did you know I like shortbread?”

“I asked Edelgard, she was knowing your favorite bakery! I wanted to go when we returned.” 

Oh. So _that’s_ how it is.

Edelgard squeezed Byleth’s hand and gestured quietly, rubbing her finger together as if she held two coins.

“Thank you so much… I really appreciate it!,” said Bernie. Edelgard leaned in, her lips close to Byleth’s ear.

“The best guess won, dear,” she whispered. Byleth grumbled, but took a gold piece from her pouch and placed it into Edelgard’s hand. The Emperor looked satisfied with herself, and tucked it away into her crimson dress’ pocket. 

The rest of the meal passed by as usual. Dorothea and Ferdinand joined them after their baths, and they talked well into the evening, eventually moving on to a few glasses of wine. After the second Edelgard excused herself and left, claiming to be tired. Byleth knew she was most likely sneaking away to do paperwork. After her third, Byleth stood as well. 

“It has been pleasant dining with you all. I believe I will also retire for the night. Have a pleasant evening, and a good day off tomorrow,” said Byleth. After the protracted goodbyes, hugs, and arm wrestling match Caspar talked her into, she finally left, heading for the baths. 

She cleaned herself thoroughly, scraping any grime and sweat from the road off her skin and perfuming herself with floral oils, scented with carnations, cardamom, and a hint of cloves. As she bathed she formulated a plan of attack. Stepping out of her bath she used a burst of fire magic to dry her hair and put it in a simple braid. Dorothea had once told her off for not taking care of her hair, but she couldn’t be bothered to apply all the oils and masks that she had been given.

She dressed and returned to her quarters, stripping and dressing herself in lingerie, picking the black lace that she knew Edelgard liked. She kept her old room for appearances, as her relationship with Edelgard was still relatively secret, hidden from common view. Each night she warped to Edelgard’s quarters, and would warp out in the morning. 

By her account, everything was ready.

* * *

Edelgard rolled her neck as she sat at her desk, trying to ward off the stiffness that she knew she’d feel come morning. After leaving the dining hall she had taken a quick bath and settled in to get some paperwork done, the sound of her quill scratching on parchment the only sound in the room.

She had taken the old Archbishop’s quarters when they had returned to Garreg Mach. They had stripped out most of the furniture and decor, it all being quite a bit too religious for Edelgard’s taste. The two pieces she kept were the desk and the bed. Even her bed in the palace wasn’t so luxurious. It was large and plush, stuffed with goose down and covered in silken sheets. 

The desk was less exciting, but it was large enough to manage multiple projects. Edelgard was searching the drawers for new bottle of ink when she heard Byleth warp in, the bright crackle of sound accompanied by the smell of ozone.

“Good evening, my beloved. Was the rest of the dinner enjoyable?,” she said. She found the bottle and uncapped it, not turning to face Byleth. She heard bare feet padding across the rug.

“It was nice. I figured I would find you here,” said Byleth. She leaned against the desk, covered by a long robe. Her perfume wafted towards Edelgard.

“Mmm, you smell divine,” she said. “I see you got a bath.”

“As did you,” said Byleth. “It’s late, and you had a long day. Your paperwork can wait until tomorrow.”

“I will be finished shortly, I just need to finish deciding logistics,” lied Edelgard. Byleth clearly didn’t buy her bullshit, and raised an eyebrow.

“Do I need to get Ferdinand to lecture you on the value of a good work-life balance, El?” Edelgard shuddered to remember the seminar that Ferdinand had given on self care. Byleth had claimed it was about swordplay, but when all was said and done she had locked herself, Edelgard, Felix, Marianne, and Ingrid inside the classroom and forced them to listen to Ferdinand wax philosophical about face masks. 

“Point taken,” said Edelgard. She capped the ink and wiped her quill clean. “You now have my full attention.” Byleth smiled devilishly.

“Good,” she said. “Now, to the main matter at hand. Our wager.”

“Ah, yes. I am so glad that Petra got her courage up,” said Edelgard. 

“My love, you cheated,” said Byleth. She ran a hand over Edelgard’s silvery locks, playing with the ends. “Petra had already asked you about the bakery.”

“I do not see how that is cheating,” said Edelgard. She knew Byleth was making the opening moves of a game, and was more than happy to play. “It was not part of our conditions that I disclose my knowledge.”

“True, but it is against the spirit of the wager,” said Byleth. She stood, walking around behind Edelgard and wrapping her muscular arms around her shoulders. “If not cheating precisely, then it was a hustle.”

“I am hurt that you think a swindler of me. If you are so mad about losing your gold piece I can add it to your budget for this coming month,” said Edelgard. Byleth’s hands began to move, slipping down her body, one ghosting the curve of her breast. 

“Darling, I think we both know this wasn’t about the gold,” said Byleth, her voice husky in Edelgard’s ear. It sent shivers down her spine.

“Then why would I cheat you?”

“Because you wanted to win,” said Byleth. “It was a power play, my love, and I was your fool. Maybe you even hoped for something.” Edelgard felt her chest flutter as Byleth’s hand dipped beneath her robe, running along the valley between her breasts and trailing lower.

“You’re a smart woman, Byleth. What do you think I hoped?,” she asked, breath hitching as Byleth pinched her nipple and rolled it between calloused fingers.

“That I would take my wager’s worth in the bedroom,” said Byleth. She nipped at Edelgard’s earlobe, drawing a hitching gasp. Edelgard felt the heat coiling in her chest, threatening to spill over.

“And now that you have me where you want me?,” she whispered, gasping as Byleth bit her neck. 

“I think you know, El,” she said. She pulled away as Edelgard whined, swiveling her chair around so she faced Edelgard. She had let her robe drop open while she was behind the chair, revealing the dark lace of her chemise and stockings. A bulge grew in her undergarments, proof of her own building desire. “I just need you to say it.”

“And deprive you the pleasure of making me?,” said Edelgard. “Never.”

Byleth said nothing, instead pushing her hand into Edelgard’s robe, slipping down to her underwear. Edelgard knew she was already wet, and Byleth’s fingers came away glistening. She smiled as she looked over Edelgard.

“You’re already wet for me, my love, and time is wasting. If you are so indecisive, I can just get myself off and make you watch,” said Byleth. “I can take my pleasure without giving you anything.”

“You wouldn’t dare,” hissed Edelgard. She straightened her back, taking on full regal bearing. “Do not forget, Dame Eisner, I am your Emperor. I will not hesitate to order you around if need be.” Edelgard enjoyed the feeling of the mask slipping on. It had become a common routine between the two, the slipping between roles and, becoming more comfortable with what once seemed profane.

“Bullshit,” said Byleth. She pulled Edelgard’s robe partially open, lowering her head to attack Edelgard’s chest. She sucked at Edelgard’s nipple, rolling it between her teeth. Edelgard gasped as she bit down, the sharp pull enough to wipe her thoughts clean momentarily. Byleth’s hands drifted down, ghosting her thighs, running over the soft skin with light touches. Edelgard whined for more, her will to resist quickly draining. “Out there you may be the Emperor, but in here? You’re mine.”

“Byleth, fuck…” moaned Edelgard, her nails scratching into Byleth’s back. Her hips bucked attempting to create more friction, But Byleth pinned down her waist with her other hand, keeping her touch light.

“I need you to say it,” said Byleth. “I won’t do a thing until you ask it of me.” Edelgard whined as Byleth bit at her collar bone, surely leaving teeth marks across her chest. 

“Goddamn,” hissed Edelgard. All attempts at propriety were gone as she squirmed, the fire in her chest stoked to a frenzy. “I need you to fuck me, By.”

“That’s not enough, my love,” said Byleth. She was clearly enjoying herself. Through the haze of lust Edelgard could see she was getting wet, too. “Be precise.”

“Fuck me with your fingers,” gasped Edelgard. She could feel herself beginning to become undone. “Please…”

“Good girl,” said Byleth. She pulled Edelgard up, carrying her to the bed. As she set her down she untied Edelgard’s robe and threw it to the floor, revealing her bare chest and soaked underwear. She took her time, palming Edelgard’s breast with one hand and peeling off her underwear with the other, slowly letting the wet linen peel off. “Goddess, you are so wet for me, El. I’m honored.”

“Please just get on with it already,” said Edelgard, the roaring in her chest quiet enough to get out a full sentence. Byleth laughed and ran her hand up Edelgard’s thigh, pinching the soft skin in her hand. 

“Good things come to those who wait, El,” she said. “But, if you insist…” Edelgard felt a finger dip inside her, her cunt accepting it easily. Byleth rocked her hand back and forward, hooking her finger tip until Edelgard felt a breathy moan escape her throat. She ground her hips down into Byleth’s hand, trying to take as much friction as she could get. 

“Fuck, By, I need more,” moaned Edelgard. Byleth kissed her, biting her lower lip and pulling. She took Edelgard’s wrists and pinned them to the bed above her head, getting above Edelgard. She pushed another finger inside, picking up speed as she thrust her fingers in and out.

Edelgard felt her mind hazing over as Byleth fucked her, the heat in her chest spreading from her core to her toes, suffusing her in warmth. A year ago she wouldn’t have been able to hope for this sort of lust, to submit, to give herself to another. Now her schoolgirl crush was fucking her into the mattress. Some dreams do come true, it seems.

Byleth kissed her as the red hot tension between her legs began to coil tighter and tighter. She was becoming rapidly unwound, panting as Byleth ruined her.

“You look so good, El,” said Byleth, her voice ragged and filled with lust. “So, beautiful spread out like that, your legs pulled open.”

“Please, please don’t stop, I’m so close…” moaned Edelgard.

“I’ve got you, El,” said Byleth, keeping a steady tempo as she drove her fingers into Edelgard over and over again. Suddenly she pressed her thumb down as she moved, bearing into Edelgard’s clit as her fingers continued to move. “Come for me, my love.”

At her words Edelgard let herself become fully unwound, the coil of pressure spilling over into a cascade. She gave a choked cry as she came, her mind going blank for one blissful second as the world dropped away, the waves of pleasure cascading through her body. She went limp against the mattress, her legs still twitching with aftershocks.

“You did so good, El,” said Byleth. She took a handkerchief from beside the bed and wiped her fingers clean, lying next to Edelgard and wrapping an arm around her waist. Edelgard turned herself, her face landing directly in Byleth’s cleavage. “Well, hello there.”

Edelgard tried to speak, but the words were muffled against Byleth’s breast. Byleth laughed, her chest thrumming with the sound. Edelgard managed to get her face free.

“I love you, By,” she murmured, her strength slowly returning.

“I love you, too, El,” said Byleth, dipping down to kiss her. “Was it worth it? Cheating?” Edelgard smiled wolfishly.

“Absolutely. Here, get on your back. I’m going to return the favor.”

  
  


**Author's Note:**

> Hello! Thanks for reading. I wrote this essentially as a test drive for writing smut, which I am new to. I am keen to write some more, so if you enjoyed this feel free to leave feedback. Thanks, friends!


End file.
